This utility notably decreases the startup time of your X sessions, provided that you start a number of X clients automatically during the X session startup. Most people, for instance, start X clients like xterm, xclock, xconsole and xosview from their .xinitrc, .openwin-init, .xtoolplaces or .xsession file. These X clients are started simultaneously (in the background) which puts a high load on the X server and the OS: * The X server is not multi-threaded, so all X clients are competing to get access to the X server and to use its resources, which causes a lot of overhead (= delay). * The performance of other (non X related) tasks served by the system degrades badly due to the high load. If the system has not enough RAM to hold all the X clients, it is swapping heavily, resulting again in a lot of delay. On the Sun platform there is a utility called 'toolwait' which solves these problems: it starts one X client in the background, waits until it has mapped a window and then exits. Xtoolwait is a free implementation of exactly the same idea. WWW: http://www.hacom.nl/~richard/software/xtoolwait.html